I just bought a 86 trx200sx for my son. I'm going though and changing all the fluids and having trouble finding the fill plug for the rear diff. Can you guys help me, how do I refill it?

 

A 200SX is chain drive. It doesn't have a differential.

 

But, it has a drain plug.

 

Doesn't the trx200sx have a rear drum brake? I wonder if you have confused the drain plug (which is used if water has gotten into the sealed brake system) for a rear differential drain plug.

budedm is correct. If it really is an sx then it is chain drive.

 

If I remember correctly, there is a bolt under the drum brake are that holds a skid plate on. Is that what you are looking at?